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Modification of simian virus 40 large tumor antigen by glycosylation
The SV40-encoded transforming protein, large tumor antigen (T-ag), is multifunctional. Chemical modifications of the T-ag polypeptide may be important for its multifunctional capacity. T-ag is additionally modified by glycosylation. T-ag was metabolically labeled in SV40-infected cells with tritiate...
Autores principales: | , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Published by Elsevier Inc.
1985
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7130735/ https://www.ncbi.nlm.nih.gov/pubmed/3002015 http://dx.doi.org/10.1016/0042-6822(85)90250-8 |
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author | Jarvis, Donald L. Butel, Janet S. |
author_facet | Jarvis, Donald L. Butel, Janet S. |
author_sort | Jarvis, Donald L. |
collection | PubMed |
description | The SV40-encoded transforming protein, large tumor antigen (T-ag), is multifunctional. Chemical modifications of the T-ag polypeptide may be important for its multifunctional capacity. T-ag is additionally modified by glycosylation. T-ag was metabolically labeled in SV40-infected cells with tritiated galactose or glucosamine, but not with mannose or fucose. The identity of glycosylated T-ag was established by immunoprecipitation with a variety of T-ag-specific antisera, including monoclonal antibodies. Incorporation of labeled sugar into T-ag was inhibited in the presence of excess unlabeled sugars, but not in the presence of excess unlabeled amino acids. Labeled monosaccharides could be preferentially removed from T-ag with a mixture of glycosidic enzymes. In addition, galactose was removed from purified T-ag by acid hydrolysis and identified as such by thin-layer chromatography. T-ag oligosaccharides were resistant to treatment with EndoH, and glycosylation was not inhibited by tunicamycin. Together, these data strongly suggest that T-ag is glycosylated. Several characteristics, including lack of mannose labeling, EndoH resistance, and tunicamycin resistance, suggest that T-ag is not an N-linked glycoprotein. Rather, these properties are more consistent with the identification of T-ag as an O-linked glycoprotein. |
format | Online Article Text |
id | pubmed-7130735 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 1985 |
publisher | Published by Elsevier Inc. |
record_format | MEDLINE/PubMed |
spelling | pubmed-71307352020-04-08 Modification of simian virus 40 large tumor antigen by glycosylation Jarvis, Donald L. Butel, Janet S. Virology Article The SV40-encoded transforming protein, large tumor antigen (T-ag), is multifunctional. Chemical modifications of the T-ag polypeptide may be important for its multifunctional capacity. T-ag is additionally modified by glycosylation. T-ag was metabolically labeled in SV40-infected cells with tritiated galactose or glucosamine, but not with mannose or fucose. The identity of glycosylated T-ag was established by immunoprecipitation with a variety of T-ag-specific antisera, including monoclonal antibodies. Incorporation of labeled sugar into T-ag was inhibited in the presence of excess unlabeled sugars, but not in the presence of excess unlabeled amino acids. Labeled monosaccharides could be preferentially removed from T-ag with a mixture of glycosidic enzymes. In addition, galactose was removed from purified T-ag by acid hydrolysis and identified as such by thin-layer chromatography. T-ag oligosaccharides were resistant to treatment with EndoH, and glycosylation was not inhibited by tunicamycin. Together, these data strongly suggest that T-ag is glycosylated. Several characteristics, including lack of mannose labeling, EndoH resistance, and tunicamycin resistance, suggest that T-ag is not an N-linked glycoprotein. Rather, these properties are more consistent with the identification of T-ag as an O-linked glycoprotein. Published by Elsevier Inc. 1985-03 2004-02-06 /pmc/articles/PMC7130735/ /pubmed/3002015 http://dx.doi.org/10.1016/0042-6822(85)90250-8 Text en Copyright © 1985 Published by Elsevier Inc. Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. |
spellingShingle | Article Jarvis, Donald L. Butel, Janet S. Modification of simian virus 40 large tumor antigen by glycosylation |
title | Modification of simian virus 40 large tumor antigen by glycosylation |
title_full | Modification of simian virus 40 large tumor antigen by glycosylation |
title_fullStr | Modification of simian virus 40 large tumor antigen by glycosylation |
title_full_unstemmed | Modification of simian virus 40 large tumor antigen by glycosylation |
title_short | Modification of simian virus 40 large tumor antigen by glycosylation |
title_sort | modification of simian virus 40 large tumor antigen by glycosylation |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7130735/ https://www.ncbi.nlm.nih.gov/pubmed/3002015 http://dx.doi.org/10.1016/0042-6822(85)90250-8 |
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